/* DESIGN TOKENS
   Breakpoint tokens document the responsive contract. Native CSS cannot use
   custom properties in media queries; matching literal queries live below. */
:root {
    color-scheme: dark;
    --color-bg: #000000;
    --color-bg-raised: #080a0d;
    --color-surface: #14181d;
    --color-surface-hover: #202730;
    --color-input: var(--color-bg-raised);
    --color-text: #f4f4f5;
    --color-muted: #b2b2bc;
    --color-subtle: #a1a1aa;
    --color-accent: #e30613;
    --color-accent-hover: #bf0510;
    --color-link: #ff3333;
    --color-link-hover: #ff4d4d;
    --color-border: #282e36;
    --color-border-strong: #65717f;
    --color-brand-mark: var(--color-accent);
    --color-glow: rgb(227 6 19 / .10);
    --card-glow: radial-gradient(ellipse at center, var(--color-glow), transparent 70%);
    --shadow-card: 0 12px 36px rgb(0 0 0 / .32);
    --shadow-panel: 0 24px 64px rgb(0 0 0 / .28);
    --font-sans: "Segoe UI", Arial, sans-serif;
    --text-xs: .75rem;
    --text-sm: .875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-card: clamp(1.25rem, 1.6vw, 1.375rem);
    --text-subtitle: clamp(1.375rem, 2.5vw, 1.75rem);
    --text-section: clamp(1.75rem, 3vw, 2.625rem);
    --text-page: clamp(2rem, 4vw, 3.5rem);
    --weight-normal: 400;
    --weight-medium: 500;
    --weight-semibold: 600;
    --weight-bold: 700;
    --leading-heading: 1.15;
    --leading-body: 1.7;
    --tracking-heading: -.035em;
    --tracking-eyebrow: .14em;
    --space-1: .25rem;
    --space-2: .5rem;
    --space-3: .75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    --space-16: 4rem;
    --space-20: 5rem;
    --space-24: 6rem;
    --radius-control: .375rem;
    --radius-card: .5rem;
    --duration-fast: 160ms;
    --duration-normal: 240ms;
    --ease-standard: cubic-bezier(.2, .6, .3, 1);
    --container-wide: 1440px;
    --container-copy: 640px;
    --container-narrow: 850px;
    --gutter: clamp(20px, 6vw, 96px);
    --section-space: clamp(48px, 6vw, 96px);
    --control-height: 48px;
    --breakpoint-nav: 1350px;
    --breakpoint-footer: 1050px;
    --breakpoint-grid: 1000px;
    --breakpoint-stack: 850px;
    --breakpoint-mobile: 600px;
    --breakpoint-compact: 480px;
}

/* BASE */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { display: flex; flex-direction: column; min-height: 100svh; background: var(--color-bg); color: var(--color-text); font-family: var(--font-sans); font-size: var(--text-base); line-height: var(--leading-body); }
main { flex: 1; min-width: 0; }
button, input, select, textarea { font: inherit; }
h1, h2, h3, h4 { color: var(--color-text); font-weight: var(--weight-bold); line-height: var(--leading-heading); letter-spacing: var(--tracking-heading); }
a { color: var(--color-link); text-underline-offset: .2em; transition: color var(--duration-fast) var(--ease-standard); }
a:hover { color: var(--color-link-hover); }
:where(a, button, summary, input, select, textarea):focus-visible { outline: 2px solid var(--color-link); outline-offset: 4px; }
[hidden] { display: none; }
.skip-link { position: absolute; top: -100px; left: var(--space-5); z-index: 20; padding: var(--space-3); background: var(--color-surface); color: var(--color-text); }
.skip-link:focus { top: var(--space-3); }

/* ACTIONS: use button + a variant for anchors or native buttons.
   Context classes below control placement only, never the button appearance. */
.button {
    display: inline-flex; align-items: center; justify-content: center; gap: var(--space-3);
    min-height: var(--control-height); padding: var(--space-3) var(--space-6);
    border: 1px solid transparent; border-radius: var(--radius-control);
    font-size: var(--text-sm); font-weight: var(--weight-semibold); line-height: 1.4;
    text-align: center; text-decoration: none; cursor: pointer;
    transition: background-color var(--duration-fast) var(--ease-standard), border-color var(--duration-fast) var(--ease-standard), color var(--duration-fast) var(--ease-standard);
}
.button--primary { color: #fff; background: var(--color-accent); border-color: var(--color-accent); }
.button--primary:hover { color: #fff; background: var(--color-accent-hover); border-color: var(--color-accent-hover); }
.button--secondary { color: var(--color-text); background: var(--color-bg-raised); border-color: var(--color-border-strong); }
.button--secondary:hover { color: var(--color-text); background: var(--color-surface-hover); border-color: var(--color-link); }
.button:disabled { opacity: .6; cursor: not-allowed; }
.button--primary:disabled:hover { background: var(--color-accent); border-color: var(--color-accent); }
.text-link { display: inline-flex; align-items: center; gap: var(--space-3); min-height: 44px; color: var(--color-link); font-size: var(--text-sm); font-weight: var(--weight-semibold); text-decoration: none; line-height: 1.5; }
.text-link:hover { color: var(--color-link-hover); }
.text-link span[aria-hidden], .button span[aria-hidden] { flex-shrink: 0; }

.contact-details { display: grid; gap: var(--space-2); margin-top: var(--space-6); font-size: var(--text-sm); font-style: normal; }
.contact-details a { display: block; width: fit-content; max-width: 100%; min-height: 44px; padding-block: var(--space-2); overflow-wrap: anywhere; }

/* HEADER AND NAVIGATION — shared by every page */
.site-header { position: relative; z-index: 10; display: flex; flex-shrink: 0; align-items: center; width: 100%; height: 80px; padding: 0 var(--space-8); background: var(--color-bg-raised); box-shadow: inset 0 -1px 0 var(--color-surface); }
.logo { color: var(--color-text); text-decoration: none; font-size: 26px; font-weight: var(--weight-bold); line-height: 1.2; margin-right: auto; white-space: nowrap; }
.logo:hover, .footer-logo:hover { color: var(--color-text); }
.logo-line, .footer-logo-line { display: block; width: 38px; height: 3px; background: var(--color-brand-mark); margin-top: var(--space-2); }
.nav-links { display: flex; align-items: center; gap: var(--space-6); }
.nav-links a, .mobile-nav a { color: var(--color-muted); text-decoration: none; font-size: var(--text-sm); font-weight: var(--weight-medium); }
.nav-links a:hover, .mobile-nav a:hover, .nav-links a[aria-current], .mobile-nav a[aria-current] { color: var(--color-link); }
.nav-links a[aria-current], .mobile-nav a[aria-current] { text-decoration: underline; }
.quote-button { margin-left: var(--space-8); white-space: nowrap; }
.mobile-menu { display: none; }

/* HOMEPAGE HERO — original photograph positioning and proportions */
/* Image fades soften the photograph's edge; header separation uses a quiet rule. */
.hero { position: relative; width: 100%; aspect-ratio: 3 / 1; background-image: linear-gradient(to top, var(--color-bg), transparent var(--space-16)), url("images/otc-welding-robot-hero.webp"); background-size: 100% 100%; background-position: center; background-repeat: no-repeat; }
.hero-content { position: absolute; left: 8%; top: 50%; transform: translateY(-50%); width: 38%; max-width: var(--container-copy); }

/* SHARED PAGE HERO */
.subpage-hero { width: 100%; padding: clamp(32px, 3vw, 48px) var(--gutter); overflow: hidden; background: var(--color-bg); }
.subpage-hero-inner { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); align-items: center; gap: clamp(24px, 2.5vw, 48px); max-width: var(--container-wide); margin: 0 auto; }
.subpage-hero-content { max-width: var(--container-copy); }
.subpage-hero-eyebrow, .robot-group-label, .enquiry-eyebrow { color: var(--color-link); font-size: var(--text-xs); font-weight: var(--weight-bold); letter-spacing: var(--tracking-eyebrow); text-transform: uppercase; }
.subpage-hero-eyebrow { display: inline-flex; align-items: center; gap: var(--space-3); margin-bottom: var(--space-5); }
.subpage-hero-eyebrow::before { content: ""; width: 24px; height: 2px; background: var(--color-link); flex-shrink: 0; }
.hero-content h1, .subpage-hero h1, .enquiry-heading h1 { font-size: var(--text-page); margin-bottom: var(--space-6); }
.hero-content p, .subpage-hero p { font-size: clamp(1rem, 1.4vw, 1.125rem); color: var(--color-muted); margin-bottom: var(--space-8); }
.subpage-hero-image { width: 100%; max-width: none; justify-self: end; transform: translateX(18px); }
.subpage-hero-image img { display: block; width: 100%; height: auto; aspect-ratio: 4 / 3; object-fit: contain; -webkit-mask-image: linear-gradient(to right, transparent, black 22%, black); mask-image: linear-gradient(to right, transparent, black 22%, black); }

/* CONTAINERS AND SECTION RHYTHM */
.categories { padding: var(--space-10) var(--gutter) var(--space-8); }
.categories-heading, .category-grid, .robot-catalogue-inner, .site-footer-inner { max-width: var(--container-wide); margin-inline: auto; }
.categories-heading, .robot-group-heading { margin-bottom: var(--space-10); }
.categories-heading h2, .robot-group-heading h2, .site-cta h2 { font-size: var(--text-section); margin-bottom: var(--space-4); }
.categories-heading p, .robot-group-heading p { color: var(--color-muted); }
.category-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-6); }

/* CARDS: common surface, border, radius and interaction */
.category-card, .robot-card { overflow: hidden; border: 1px solid var(--color-border); border-radius: var(--radius-card); background: var(--color-surface); transition: transform var(--duration-normal) var(--ease-standard), border-color var(--duration-normal) var(--ease-standard), box-shadow var(--duration-normal) var(--ease-standard); }
.category-card:hover, .robot-card:hover { transform: translateY(-3px); border-color: var(--color-link); box-shadow: var(--shadow-card); }
.category-card { position: relative; display: block; aspect-ratio: 4 / 3; text-decoration: none; }
.category-card img { width: 100%; height: 100%; object-fit: cover; display: block; transition: transform var(--duration-normal) var(--ease-standard); }
.category-card:hover img { transform: scale(1.025); }
.category-card::after { content: ""; position: absolute; inset: 0; background: linear-gradient(to top, rgb(0 0 0 / .85), transparent 65%), var(--card-glow); pointer-events: none; }
.category-card h3 { position: absolute; bottom: var(--space-6); left: var(--space-6); right: var(--space-6); z-index: 1; font-size: var(--text-card); font-weight: var(--weight-semibold); display: flex; justify-content: space-between; align-items: center; gap: var(--space-3); }
.category-card span { color: var(--color-link); }

/* ROBOT CATALOGUE — flex retains centred incomplete rows */
.robot-catalogue { width: 100%; padding: var(--space-10) var(--gutter) var(--section-space); }
.robot-group + .robot-group { margin-top: var(--section-space); }
.robot-group-label { display: block; margin-bottom: var(--space-3); }
.robot-subgroup + .robot-subgroup { margin-top: var(--space-16); }
.robot-subgroup-heading { margin-bottom: var(--space-8); padding-left: var(--space-4); border-left: 2px solid var(--color-link); font-size: var(--text-subtitle); font-weight: var(--weight-semibold); }
.robot-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: var(--space-6); }
.robot-card { flex: 0 1 calc((100% - var(--space-6) * 2) / 3); min-width: 0; }
.robot-card-media { display: flex; align-items: center; justify-content: center; width: 100%; aspect-ratio: 4 / 3; overflow: hidden; background-color: var(--color-bg-raised); background-image: var(--card-glow), linear-gradient(var(--color-bg-raised), var(--color-surface)); }
.robot-card-media img { display: block; width: 100%; height: 100%; padding: var(--space-4); object-fit: contain; }
.robot-card-media > span { color: var(--color-subtle); font-size: var(--text-xs); letter-spacing: .1em; }
.robot-card-content { padding: var(--space-6); }
.robot-card-content h3, .robot-card-content h4 { font-size: var(--text-card); font-weight: var(--weight-semibold); margin-bottom: var(--space-3); }
.robot-card-content p { color: var(--color-muted); font-size: var(--text-sm); margin-bottom: var(--space-4); }

/* PROCESS GUIDES — shared educational sections on product pages */
.process-guide {
    padding: var(--section-space) var(--gutter);
    background: var(--color-bg-raised);
    border-block: 1px solid var(--color-border);
}
.process-guide-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-10); }
.process-explainer { padding-left: var(--space-6); border-left: 2px solid var(--color-accent); }
.process-explainer h3 { margin-bottom: var(--space-4); font-size: var(--text-subtitle); }
.process-explainer p { max-width: var(--container-copy); color: var(--color-muted); }
.process-explainer--wide { grid-column: 1 / -1; }
.process-explainer--wide p { max-width: none; }
.process-explainer p + p { margin-top: var(--space-4); }
.process-explainer strong, .process-guide-note strong { color: var(--color-text); font-weight: var(--weight-semibold); }
.process-guide-note { margin-top: var(--space-10); padding-top: var(--space-6); border-top: 1px solid var(--color-border); color: var(--color-muted); font-size: var(--text-sm); }

/* CONVERSION SECTION */
.site-cta {
    width: 100%;
    padding: clamp(var(--space-12), 8vw, var(--space-24)) var(--gutter);
    text-align: center;
    background: linear-gradient(to bottom, var(--color-bg), var(--color-bg-raised));
}
.site-cta-inner { max-width: var(--container-narrow); margin: auto; }
.site-cta p { max-width: var(--container-copy); margin: 0 auto var(--space-6); color: var(--color-muted); font-size: var(--text-lg); }
.site-cta-buttons { display: flex; justify-content: center; flex-wrap: wrap; gap: var(--space-4); }
.site-cta-button { min-width: 190px; }

/* FORMS: shared controls; enquiry layout remains in enquiries.css */
.form-field { min-width: 0; }
.form-field label { display: block; font-size: var(--text-sm); font-weight: var(--weight-semibold); margin-bottom: var(--space-2); line-height: 1.5; }
.form-field label span { font-size: var(--text-xs); font-weight: var(--weight-normal); color: var(--color-muted); }
.form-field :is(input, select, textarea) { display: block; width: 100%; min-width: 0; min-height: var(--control-height); border: 1px solid var(--color-border-strong); border-radius: var(--radius-control); background: var(--color-input); color: var(--color-text); padding: var(--space-3) var(--space-4); font-size: var(--text-base); line-height: 1.5; transition: border-color var(--duration-fast) var(--ease-standard); }
.form-field textarea { resize: vertical; line-height: var(--leading-body); }
.form-field :is(input, textarea)::placeholder { color: var(--color-subtle); font-size: var(--text-sm); }
.form-field :is(input, select, textarea):hover { border-color: var(--color-link); }
.form-field :is(input, select, textarea):focus-visible { border-color: var(--color-link); }

/* FOOTER: shared full-width grid on every page */
.site-footer { flex-shrink: 0; padding: var(--space-8) var(--gutter) var(--space-6); background: var(--color-bg-raised); border-top: 1px solid var(--color-surface); color: var(--color-muted); font-size: var(--text-sm); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: var(--space-12); padding-bottom: var(--space-12); }
.footer-logo { display: inline-block; color: var(--color-text); font-size: var(--text-card); font-weight: var(--weight-bold); text-decoration: none; line-height: 1.2; }
.footer-brand p { max-width: 320px; margin-top: var(--space-6); }
.footer-brand .footer-partner { color: var(--color-subtle); font-size: var(--text-xs); }
.footer-partner strong { color: var(--color-text); }
.footer-column { display: flex; flex-direction: column; align-items: flex-start; gap: var(--space-3); }
.footer-column h2 { font-size: var(--text-base); letter-spacing: 0; margin-bottom: var(--space-2); }
.site-footer a:not(.footer-logo) { color: var(--color-muted); text-decoration: none; }
.site-footer a:not(.footer-logo):hover { color: var(--color-link-hover); }
.site-footer .footer-partner a { color: var(--color-text); text-decoration: underline; }
.site-footer a[aria-current] { color: var(--color-link); text-decoration: underline; }
.footer-social { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-2); width: 100%; margin-top: var(--space-2); }
.footer-social-link { display: flex; align-items: center; gap: var(--space-2); min-width: 0; min-height: 44px; padding: var(--space-3); background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-control); font-size: var(--text-xs); transition: border-color var(--duration-fast) var(--ease-standard), background-color var(--duration-fast) var(--ease-standard); }
.footer-social-link svg { width: 19px; height: 19px; flex-shrink: 0; }
.footer-social-link:hover { background: var(--color-surface-hover); border-color: var(--color-link); }
.site-footer-bottom { display: flex; justify-content: space-between; align-items: center; gap: var(--space-5); padding-top: var(--space-6); border-top: 1px solid var(--color-surface); font-size: var(--text-xs); }
.footer-image-notice { margin-bottom: var(--space-6); font-size: var(--text-xs); }
.footer-legal { display: flex; flex-wrap: wrap; gap: var(--space-6); }

/* RESPONSIVE CONTRACT — literal values match the documented tokens above */
@media (max-width: 1350px) {
    .site-header { height: 72px; padding-inline: var(--space-5); }
    .logo { font-size: 20px; }
    .nav-links { display: none; }
    .quote-button { margin-left: var(--space-3); margin-right: var(--space-4); padding-inline: var(--space-4); }
    .mobile-menu { display: block; flex-shrink: 0; }
    .mobile-menu summary { display: flex; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; cursor: pointer; list-style: none; font-size: 24px; line-height: 1; }
    .mobile-menu summary::-webkit-details-marker { display: none; }
    .mobile-nav { position: absolute; top: 100%; left: 0; right: 0; display: flex; flex-direction: column; padding: var(--space-4) var(--space-5); max-height: calc(100dvh - 72px); overflow-y: auto; background: var(--color-bg-raised); border-bottom: 1px solid var(--color-surface); box-shadow: var(--shadow-card); }
    .mobile-nav a { display: flex; align-items: center; min-height: 44px; }
}
@media (max-width: 1050px) { .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-10); } }
@media (max-width: 1000px) {
    .category-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .robot-card { flex-basis: calc((100% - var(--space-6)) / 2); }
    /* Stack earlier on tablets so the larger shared CTA fits above the image. */
    .hero { aspect-ratio: auto; background-image: none; }
    .hero-content { position: static; transform: none; width: 100%; max-width: none; padding: var(--space-10) var(--gutter) var(--space-8); }
    .hero::after { content: ""; display: block; width: 100%; aspect-ratio: 3 / 2; background: linear-gradient(to top, var(--color-bg), transparent var(--space-16)), url("images/otc-welding-robot-hero-mobile.webp") center / cover no-repeat; }
}
@media (max-width: 850px) {
    .subpage-hero { padding-block: var(--space-10) var(--space-12); }
    .subpage-hero-inner { grid-template-columns: minmax(0, 1fr); gap: var(--space-8); }
    .subpage-hero-content { max-width: 100%; }
    .subpage-hero-image { max-width: 100%; transform: none; }
    .subpage-hero-image img { -webkit-mask-image: none; mask-image: none; }
}
@media (max-width: 600px) {
    .process-guide-grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-8); }
    .site-cta-buttons { flex-direction: column; align-items: stretch; }
    .site-cta-button { width: 100%; }
    .footer-grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-8); padding-bottom: var(--space-10); }
    .footer-social { max-width: 340px; }
    .site-footer-bottom { flex-direction: column; align-items: flex-start; gap: var(--space-4); }
    .categories { padding-top: var(--section-space); }
    .category-grid { grid-template-columns: minmax(0, 1fr); }
    .robot-subgroup + .robot-subgroup { margin-top: var(--space-12); }
    .robot-card { flex-basis: 100%; }
    .robot-card-content { padding: var(--space-5); }
}
@media (max-width: 480px) {
    .site-header { padding-inline: var(--space-2); gap: var(--space-1); }
    .logo { font-size: clamp(var(--text-sm), 4vw, 15px); }
    .quote-button { margin: 0; padding-inline: var(--space-1); font-size: var(--text-xs); flex-shrink: 0; }
}
@media (prefers-reduced-motion: reduce) {
    :root { --duration-fast: 0ms; --duration-normal: 0ms; }
    .category-card:hover, .robot-card:hover, .category-card:hover img { transform: none; }
}